Today we're launching another game, Renegade Ops just went live for consoles, and the PC version is coming to Steam shortly. And by "we" I mean my fellow colleagues here at Avalanche Studios. I am not and have not been part of the Renegade Ops team, so my main contribution has been my constant "is it done yet?" nagging and dropping a few puns on occasion at their desks. Despite not being on the team I'm very excited about this title. It's just plainly a cool game. I'll have to wait for another little while though, because I'll be playing on the PC. The game was developed by a small team with a small budget and shorter development time than usual, so I'm impressed with what they have been able to accomplish. And best of all is that it also comes at a small price tag. €13 on Steam, or €25 for a pack of 4 for those of you who want to play online co-op.

With the public release of the Windows 8 Developer Preview the documentation for the upcoming DirectX 11.1 API has made it online as well. It's preliminary and subject to change of course, but likely the changes won't be too dramatic. The list of new features and additions is pretty long for a mere ".1" update.

I have added a new gallery to my pictures. These are pictures of my pregnant wife from her 7th month. Now we're in the final month with just over two weeks left to the projected birth date, so it's time I put these pictures up before mini-Humus arrives.

I have just posted another demo of yet another anti-aliasing technique. I call it Second-Depth Anti-Aliasing (SDAA) since it requires the second depths in the scene, i.e. the depths of the backfaces. Quality-wise it rivals that of GPAA/GBAA and is easier to integrate into an existing engine.

I have updated the GBAA demo with a few fixes to performance and image quality. The most glaring oversight I did in the previous version was that I made a copy of the backbuffer for the last resolve pass to read. I tend to copy an old demo and start from that rather than setting up everything from scratch. In this case I copied the GPAA demo and it didn't pass my mind that the backbuffer copy that was necessary for GPAA is not necessary when you have a final fullscreen pass like in GBAA. Instead you can just render to a temporary render target and read that while writing to the backbuffer in the end. This buffer copy was nearly half the cost of the resolve process, so eliminating this is significant win. The other thing I did was to only clear the buffers that need it, i.e. the depth buffer and geometry buffer. I could have removed the geometry buffer clear too, but felt it was good for educational purposes to leave it there, plus I would have had to change the skybox pass to accommodate the change, so it wouldn't necessarily be a win in all cases. For image quality I changed the unused component to be 0.5 instead of 0. This is to avoid the case where the distance computation landed exactly on zero, which would be interpreted as "no edge here" rather than edge cutting through pixel center. This resulted in some rare single pixel errors, especially for lower precision formats like RG8S. This demo is still using RG16F though because I saw nearly no performance gain to go down to RG8S.

There is a new demo up demonstrating another anti-aliasing technique called GBAA (Geometry Buffer Anti-Aliasing). Like GPAA it uses actual geometry information, but stores it in a fullscreen buffer. This should scale better with dense geometry and additionally allows alpha-tested edges to be anti-aliased.

So it's been a little while since my last post. The main reason for that is that I'm in the middle of moving to a new apartment and trying to sell the one I'm living in now, and for most of the time my main computer has been packed into a box. I'll be stuck on my laptop for a while yet, but everything will be back to normal soon.

So what's new?
1) I'll be talking at Siggraph in the Filtering Approaches for Real-Time Anti-Aliasing course. I'll be covering a technique called Geometry Buffer Anti-Aliasing, a technique I have a working prototype of on my main computer, but haven't had the chance to release yet because my computer is in a box, but once that's resolved I will release a demo of it.
2) I'll be covering about the same topic in GPU Pro 3.
3) My wife's belly is getting larger by the day and we're both getting increasingly excited about becoming parents. 4) After signing up to Twitter I was taken by surprise by the amount of people who cared enough to follow my tiny bits of wisdom and mini-rants. The first days my mailbox to spammed to death by "[xyz] is now following you on twitter" email, which was interesting. Now it's more of a steady trickle, which is interesting to watch and find out what kind of people are following me. If you didn't sign up yet, you can find me here.